Apparatus for correcting parameters of the cut made by a paper guillotine, and a paper guillotine having such apparatus

ABSTRACT

Paper guillotines can perform repeated cutting cycles in accordance with a predetermined programme which controls the motion of a feed slide of the guillotine; in order to avoid the necessity for manual corrections during the whole course of the programme, I provide an electronic cut correction store so that corrections made by an operator during a first cutting cycle can be fed into the store and used to make the same corrections during subsequent cutting cycles.

United States Patent Mohr 1 Feb. 19 1974 i 1 APPARATUS FOR CORRECTING [56] References Cited PARAMETERS OF THE C UT MADE BY A UNITED TE TENT PAPER GUILLOTINE AND A PAPER 3,623,619 11 1971 Loper v. 214/].6

GUILLOTINE HAVING SUCH APPARATUS Rudolf Mohr, Hattersheimerstrasse, Hofheim Taunus, Germany Filed: July 28, 1972 Appl. No.: 276,158

Inventor:

Foreign Application Priority Data Aug. 2, 1971 Germany 2138499 U.S. Cl 83/71, 83/73, 83/278,

214/1.6 Int. Cl B26d 7/06, B65h 7/00 Field of Search 83/71, 278, 73; 214/16 Primary Examiner-J. M. Meister Attorney, Agent, or Firm-Holman & Stern [57] ABSTRACT Paper guillotines can perform repeated cutting cycles in accordance with a predetermined programme which controls the motion of a feed slide of the guillotine; in order to avoid the necessity for manual corrections during the whole course of the programme, I providevan electronic cut correction store so that corrections made by an operator during a first cutting cycle can be fed into the store and used to make the same corrections during subsequent cutting cycles.

7 Claims, 4 Drawing Figures PAIENIEB Y 3. 792 6 3 sum 1 or 4 APPARATUS FOR CORRECTING PARAMETERS OF THE CUT MADE BY A PAPER GUILLOTINE, AND A PAPER GUILLOTINE HAVING SUCH APPARATUS BACKGROUND OF THE INVENTION This invention relates to apparatus for correcting parameters of the cut made by a paper guillotine having automatic means for performing repeated cutting cycles in accordance with a predetermined programme.

The individual cutting parameters for the guillotine are stored on a programme carrier, for example a magnetic tape, in order to perform a cutting programme. The magnetic tape will then control the motions of the feed slide of a guillotine so that the cuts may be automatically performed.

If printed sheets are to be cut, it is necessary for the cut to be made precisely on a predetermined cutting line on the printed sheet so that each printed sheet is available in the same size after the cut is made. Frequent corrections during the cutting programme are necessary for this type of cut (a so-called label cut) since the distances between the cutting lines vary to some extent. These differences occur during printing due to the use of uneven rollers and furthermore owing to the fact that the moisture content of the printing ink and the different printing ink thickness causes the sheets to distort.

Moreover, the printed image varies due to the stack ing of the printed material because the sheets in the lower part of the stack are stretched more than the sheets in the upper part of the stack owing to the greater pressure acting on the lower sheets.

Furthermore, during the actual cutting operation, the individual sheets of a ream are subject to different changes of length since the press beam pulls the upper sheets of the ream towards the guillotine blade.

Due to these effects, it is necessary for the longitudinal position, angular position and angle of inclination of the ream to be corrected during the cutting programme in order to obtain a precise cutting sequence.

PRIOR TECHNIQUE Accordingly it was necessary for the cutting performance to be constantly monitored. Deviations from the specified cutting line necessitate an interruption of the cutting operation, and the ream had to be moved manually into the precise position to eliminate the deviations. This was done by the insertion of cardboard or like strips between the ream and the slide.

These manual corrections took a substantial amount of time so that the time gained by the fully'automatic method of operation of the guillotine was to some extent lost.

In practical operation it was found that these corrections are required after a definite number of cuts or after a definite number of reams have been cut, that is to say, in a constant sequence or cycle.

SUMMARY OF THE INVENTION The present invention provides apparatus for correcting parameters of the cut made by a paper guillotine having automatic. means for performing repeated cutting cycles in accordance with a predetermined programme, the apparatus having means for correcting parameters of the cut and an electronic cut correction store for storing cut corrections made by an operator during a first cutting cycle and causing the correcting means to repeat the cut corrections during subsequent cutting cycles. The invention also provides a paper guillotine having automatic means for performing repeated cutting cycles in accordance with a predetermined programme, having the apparatus of the invention.

Values of length correction and angle correction in the horizontal and vertical planes can be programmed into the cut correction store. Thus all important changes in the cutting programme can be made and programmed into the cut correction store so that the cutting operation can subsequently proceed automatically for the entire cutting programme, without any form of supervision. The guillotine will have a feed slide controlled by said automatic means, and a correction member is preferably connected to the feed slide for movement therewith and for moving paper being cut by the guillotine, with the correction member being movable relative to the feed slide for correcting at least some of said parameters; in the course of the cutting programme, all correction values can be transferred in the appropriate sequence to the correction member (which may be a rake), for moving the ream automatically into the corrected cutting position.

The invention will be further described, by way of example, with reference to the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a function and control diagram of apparatus for correcting parameters of the cut made by a paper guillotine, the guillotine having automatic means for performing repeated cutting cycles in accordance with a predetermined programme;

FIG. 2 is a plan view, partly in horizontal section, of the feed slide and correction member of the guillotine, when performing an angle correction;

FIG. 3 is a plan view, partly in horizontal section, of the feed slide and correction member, when performing a length correction; and

FIG. 4 is a vertical section through the feed slide and correction member, when performing an inclination correction.

DETAILED DESCRIPTION OF THE INVENTION As illustrated in FIGS. 2, 3 and 4, a feed slide 1 is slid ably disposed on a work-table of a paper guillotine which is not shown. The front of the feed slide I accommodates a correction member in the form of a rake 2 which is supported for universal movement in recesses 3 of the slide 1. In the initial position, rear end face 4 of the rake 2 bears on front end face 5 of the slide while a ream 6 to be cut bears on front end 7 of the rake 2. In its initial position, the rake 2 is maintained in contact with the slide 1 by springs 8. To adjust the rake 2 on the slide 1, the latter is provided with two bearings 9 in which guide pins 10 are guided so as to be longitudinally slidable. The guide pins 10 are guided in appropriate bearings 11 on the rake 2 and may be retained therein by means of releasable locking means in the form of pins 12.

The rake is also provided with positioning markers 13 which may be adjusted in the rake 2, irrespective of the motion thereof, by the guide pins 10 if the locking pins are released. Adjusting spindles 14, coupled to servomotors 15, act on the guide pins 10. The servomotors are equipped with contact discs 16, so-called distance transmitters, whose rotation is synchronized with that of the servomotors.

In the position of the rake 2 illustrated in FIG. 2, the rake is displaced relative to the slide 1 by an amount X into a corresponding angular position in the horizontal plane. This displacement is necessary if the printed cutting line is not in alignment with the cutting line of the guillotine blade. As may be seen by reference to FIG. 2, the ream 6 is moved in the course of this angular adjustment from the position indicated by the solid lines into the position indicated by the dash-dot lines. The amount of displacement therefore corresponds to the required correction. Only one servomotor is operative for the angular adjustment shown in FIG. 2.

If a correction of the ream is required in accordance with FIG. 3, both servomotors 15 are switched on so that the correcting rake moves forward parallel to the slide and the ream is moved from the position illustrated in solid lines into the position illustrated by dashdot lines.

If the individual sheet lengths of the ream have altered during the cutting operation due to the effect of the press-beam of the guillotine, that is to say if the upper sheet lengths have become shorter, a correction is required in accordance with FIG. 4. This correction is made by changing the angle ofinclination of the correction rake 2. In the initial position, the correction rake 2 is disposed perpendicular to the work-table. This adjustment is made in the same way as for the adjustment illustrated in FIGS. 2 and 3 through a servomotor 15 which moves the correction rake by means of a worm drive 17 from the basic position into the correct ing position 18 while in effect pivoting the ream 6 through an angle X All these corrections are fed into a storage unit 19 (FIG. 1) and are programmed into the cutting programme so that the cutting programme, which is on a magnetic tape, is provided with the necessary corrections at the appropriate time.

Practical experience has shown that cutting corrections are required during the cutting routine of a ream and further corrections must be performed after a plurality of reams have been cut. In order to' allow for these circumstances in their entirety and in a precise sequence when storing the correction dimensions, it is necessary to feed the number of cuts and the number of reams into the storage unit 19.

The routine is illustrated in the function and control diagram according to FIG. 1. The control function relating to a change of angle of inclination of the correcting rake is not plotted in this diagram in the interests of clarity. The last-mentioned function is analogous to the control function for the change of angle or length of the correcting rake in accordance with FIGS. 2 and 3.

The method of operation is explained below by reference to the control diagram of FIG. 1.

In the initial position, that is to say, before the cutting programme is performed, the correction rake 2 bears on the slide 1. If the first ream is placed on the worktable and brought to bear against the correction rake, this function will be stored in the storage unit 19 by a ream counter 20. The cuts are then performed in the usual manner. If it is found that a correction of the angular position in accordance with FIG. 2 is required after a plurality ofcuts have been made, which are also stored in the storage unit 19 by a cut counter 21, the operator depresses a switch button 22 of a control unit 23, thus switching on the control motor 15. The motor 15 is synchronized with a distance transmitter whose contact points 24 co-operate with a contact point 25 to feed separate pulses into the storage unit. For example, if the correction position of the slide 1 is adjusted in accordance with FIG. 2 when the fourth contact point 26 is reached, four pulses will be given by a signal transmitter 27 and stored in the storage unit 19. The number of reams, the number of cuts and the correction which is fed to the control unit for operating the servomotors and the final control elements, in accordance with these numerical values in the course of the cutting programme, are thus stored in the storage unit 19.

The same process is repeated if the corrections in the longutudinal direction of the correction rake 2 or ofthe angle of inclination thereof become necessary in the course of further cutting sequences. Feed-in of the correction values is therefore necessary only once because it has been found that these corrections remain constant over a specific number of reams and a specific number of cutting sequences. For example, if the cutting programme covers 1,000 reams with the same printing pattern, stacked in ten stacks by 10 pallets to form a complete stack, it is merely necessary to correct the cutting routine or cycle for the first stack and to programme the corrections into the control unit since these values remain the same for the remaining nine stacks.

When a control button 28 is operated, the two servo motors 15 are actuated so that the correction rake 2 moves forward parallel to the slide 1. Both distance transmitters 16 will then deliver the corresponding number of pulses via the signal transmitter 27 into the storage unit 19.

The cutting programme proceeds therefore completely automatically for all succeeding stacks after the first stack has been cut.

Adjustment of the position may also be performed by means of the positioning markers 13, to which end it is merely necessary to release the locking pins 12 so that the positioning markers 13 may be moved into the desired position independently of the correction rake.

After feeding in all corrections required for cutting the stack, the storage unit 19 will transfer the data to the control unit 23 which then controls the servomotors 15 with the control elements for operating the correction rake 2 in the manner described above.

I claim:

1. In a paper guillotine comprising a blade, a feed slide for feeding paper to the blade and automatic means for performing repeated cutting cycles in accor dance with a predetermined programme, apparatus for correcting parameters of the cut, the apparatus comprising means for correcting parameters of the cut and an electronic cut correction store means for storing cut corrections made by an operator during a first cutting cycle and associated with the correcting means to repeate the cut corrections during subsequent cutting cycles, wherein said parameters are the values of longitudinal correction and angular correction in the horizontal and vertical plane.

2. In a paper guillotine comprising a blade, a feed slide for feeding paper to the blase and automatic means for performing repeated cutting cycles in accordance with a predetermined programme, apparatus for correcting parameters of the cut, the apparatus comprising means for correcting parameters of the cut and an electronic cut correction store means for storing cut corrections made by an operator during a first cutting cycle and associated with the correcting means to repeate the cut corrections during subsequent cutting cycles, wherein the correction store means comprises a control unit for control by an operator to feed in corrections, and the correcting means comprises motors for making the corrections, and cooperating movable members and signal transmitters for giving signals corresponding to the corrections made by the motors.

3. In a paper guillotine comprising a blade, a feed slide for feeding paper to the blade and automatic means for performing repeated cutting cycles in accordance with a predetermined programme, apparatus for correcting parameters of the cut, the apparatus comprising means for correcting parameters of the cut and an electronic cut correcting store means for storing cut corrections made by an operator during a first cutting cycle and associated with the correcting means to repeate the cut corrections during subsequent cutting cycles, and including a correction member connected to the feed slide of the guillotine and movable relative to the feed slide for correcting at least one of said parameters.

4. The apparatus as claimed in claim 3, wherein the correction member is connected to the feed slide such that the correction member can move universally relative thereto.

5. The apparatus as claimed in claim 4, wherein the correction member is connected to the feed slide by guide pins, said correcting means comprising control elements for moving the correction member relative to the feed slide, and the guide pins being operatively connected to the control elements.

6. The apparatus as claimed in claim 5, wherein the guide pins are fixed to the correction member by means of releasable locking means.

7. The apparatus as claimed in claim 6, wherein the correction member is provided with positioning markers which can be actuated by the guide pins, independently of the correction member, after the locking means have been released. 

1. In a paper guillotine comprising a blade, a feed slide for feeding paper to the blade and automatic means for performing repeated cutting cycles in accordance with a predetermined programme, apparatus for correcting parameters of the cut, the apparatus comprising means for correcting parameters of the cut and an electronic cut correction store means for storing cut corrections made by an operator during a first cutting cycle and associated with the correcting means to repeate the cut corrections during subsequent cutting cycles, wherein said parameters are the values of longitudinal correction and angular correction in the horizontal and vertical plane.
 2. In a paper guillotine comprising a blade, a feed slide for feeding paper to the blade and automatic means for performing repeated cutting cycles in accordance with a predetermined programme, apparatus for correcting parameters of the cut, the apparatus comprising means for correcting parameters of the cut and an electronic cut correction store means for storing cut corrections made by an operator during a first cutting cycle and associated with the correcting means to repeate the cut corrections during subsequent cutting cycles, wherein the correction store means comprises a control unit for control by an operator to feed in corrections, and the correcting means comprises motors for making the corrections, and cooperating movable members and signal transmitters for giving signals corresponding to the corrections made by the motors.
 3. In a paper guillotine comprising a blade, a feed slide for feeding paper to the blade and automatic means for performing repeated cutting cycles in accordance with a predetermined programme, apparatus for correcting parameters of the cut, the apparatus comprising means for correcting parameters of the cut and an electronic cut correcting store means for storing cut corrections made by an operator during a first cutting cycle and associated with the correcting means to repeate the cut corrections during subsequent cutting cycles, and including a correction member connected to the feed slide of the guillotine and movable relative to the feed slide for correcting at least one of said parameters.
 4. The apparatus as claimed in claim 3, wherein the correction member is connected to the feed slide such that the correction member can move universally relative thereto.
 5. The apparatus as claimed in claim 4, wherein the correction member is connected to the feed slide by guide pins, said correcting means comprising control elements for moving the correction member relative to the feed slide, and the guide pins being operatively connected to the control elements.
 6. The apparatus as claimed in claim 5, wherein the guide pins are fixed to the cOrrection member by means of releasable locking means.
 7. The apparatus as claimed in claim 6, wherein the correction member is provided with positioning markers which can be actuated by the guide pins, independently of the correction member, after the locking means have been released. 